Bendable printing plate



Patented May 19, 1925.

UNITED STATES PAUL FOCKE, O1' BABIEN, GERIANY.

BENDABLE PRINTING PLATE.

Application flled August 18, 1920. Serial R0. 404,038.

T all whom it may concern:

Be it known that I, PAUL FooKE, a citizen of the German Republic, residing at Barmen, Rhenish Prussia, Germany, have in- 5 vented certain new and useful Improvements in Bendable Printing Plates (for which I have filed an application in Germany, April 9, 1918), of which the following is a specification.

My invention relates' to a printing plate for reproducing and manifolding typewritten matter such as letters, circulars and the like. by means of planographic printing processes. These processes which compriSe the lithographic and the so-called off-set printing art are recognized as being particularly adapted to mass production of prints of high quality, but these processes are somewhat complicated and more so in cases where typewritten matter is to be nianifolded, for a number of intricate Operations are involved fin the transference of the original ty escript to the printing plate proper, an these various 25 ransfer Operations usually require skilled abor.

The object of my invention is to provide a printing plate for simplifying the primary Operations involved in planographlc processes, that is, to facilitate the reparing of the printing plates proper carrying the typewritten matter to be printed therefrom, so as to enable even unskilled persons to use planographic machines/ for reproducing typewritten copies of a high class character in large quantities. With this and other objects in view I provide for the purpose set forth a planographic printing medium which consists of a relatively very thin sheet presenting a hard metallic surface and being pliable to an extent sufficient to be introduced into, and fed through, a typewriting machine for receiving the typescript to be printed from the sheet. The said planographic printing medium may consist of very thin sheet of zinc, preferably free of lead, or other metal, adapted to be used for planographic printing. Experiments have shown that paper or thin and highly flexible card-board having a hard metallized surface or a thin metal coat are lalso suitable media adapted to receive inscriptions on typewriting machines according to this invention and thereupon to serve as print1ng lates proper in planographic printing mac lines.

The metallic surface of said printing medium should be grained and hard enough to not show for a reasonable length of service any wear due tobeing bent about the typewriter platen and being pounded by the type levers, so that the same plate may be used over and over again. The ribbon or other inking device used in the typewriter for Writing on the planographic printing medium must carry transfer ink as used in the lithographic art.

How the printing is actually done in practice on an off-set printing machine is described by way of an example in the following part of the specification with reference to the accompanying drawing which diagrammatically shows a Sectional elevation of an off-set printing machine.

The highly flexible planographic printing plate a is first introduced into a typewriting machine and therein receives the typescri with a ribbon carrying lithographic inli. After the typescript has dried upon the printingplate, the latter is dusted with talc and lightly etched with a solution of phosphoric acid and gum arabic. whereupon the printing plate is dried, washed and finally inked in the usual way.

As diagrammatically indicated in the drawing, the printing plate a, carrying the typescript ready for printing, is then attached to the upper roller b of the off-set printing press, the latter being provided with a moistening roller c and inking rollers d.

From the roller b the typescriptis first transferred or set ofl' to the roller e coated With rubber on which the design will appear in negative configuration. By means of a third roller f, cooperating with the transfer roller b the paper or other suitable material is imprinted With the typescript.

It is obvious that .the typewritten matter on the planographic plate ma be conveniently supplemental with han -written signatures, drawings, and any other design as called for in each individual case, without deviating from the spirit of my invention.

For what I claim protection under Letters Patent is:

1. A planographic printing plate for reproducing typewritten matter, which con- 6 sists of a relativel thin sheet presenting a hard metallic sur ace and being pliable to an extent suflicient to be introduced into typewriting machines and to receive the typescript to be printed from the sheet.

2. A printing plate according to claim 1 1 Which consists of a very thin sheet of zine.

In testimony whereof I have signed my name.

' PAUL FOCKE. 

